In addition to his previous conviction for attacking police, he was also known to the force for other criminality including theft and violence.
The French government pulled out all the stops to protect Sunday's vote as the attack deepened France's political divide.
Speaking Friday on RTL radio, Macron said: "What our attackers want is death, symbolism, to sow panic (and) to disturb a democratic process, which is the presidential election".
"Barbarity and cowardice struck Paris last night", the prime minister said, appealing for national unity and for people "not to succumb to fear".
The attacker, identified as French national Karim Cheurfi, was later killed by police during the Thursday night shootout, the Guardian reported.
On Thursday night, the attacker stepped out from a auto with an automatic rifle and opened fire on a police van outside a Marks & Spencer store on the Champs Élysées in central Paris.
The gunman, who was shot dead by police, had a long criminal record, a source close to the investigation told CNN. Cheurfi's identity was confirmed from his fingerprints. He had been arrested in February on suspicion of plotting to kill police officers but released for lack of evidence. Its president, Mickael Bucheron, told AP the slain officer would have celebrated his 38th birthday at the beginning of May.
Two other officers were seriously wounded in the attack in the popular tourist area in central Paris.
"This concert's to celebrate life". The Islamic State group claims responsibility for the attack carried out by a jihadist with a prior terrorist conviction.
ISIS has claimed credit for the attack. The people of France will not take much more of this. Delivery trucks did their early morning rounds.
Le Pen, who has campaigned on an anti-European Union, anti-immigration platform, was the only major French candidate who backed Republican Trump in the November 8 USA presidential election. Sunday's round of voting will be followed by a second-round runoff on May 7 between the top two candidates.
The attack brought back the recurrent campaign theme of France's fight against Islamic extremism, one of the mainstays of the anti-immigration platform of far-right leader Marine Le Pen and also, to a lesser extent, of Fillon.
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Macron, a former economy minister in the government that Le Pen has criticised repeatedly for its security record, said the solutions were not as simple as she suggested. Cazeneuve, the Socialist prime minister, accused the National Front leader of seeking to make political hay from the assault.
At a televised news conference Friday, Le Pen called for the closure of all Islamist mosques in France, the expulsion of hate preachers and the reinstatement of French borders.
He said: "She seems to be deliberately forgetting everything that has been done over five years to make people forget that she opposed everything, without ever proposing anything serious or credible".
With some voters doubtful whether the 39-year-old former banker is experienced enough to be head of state, Macron appealed for cool heads.
Conservative contender Francois Fillon, who has campaigned against "Islamic totalitarianism", said on France 2 television that he was canceling his planned campaign stops Friday.
"She won't be able to protect our citizens", Macron said. He added that there was nothing in the shooting investigation linking immigration to the incident.
The attacker emerged from a auto and used an automatic weapon to shoot at officers outside a Marks & Spencer's department store at the center of the Champs-Elysees.
German Chancellor Angela Merkel said her sympathy "goes out to the victims and their families", according to her spokesman Steffen Seibert.
The attack appeared to fit a spreading pattern of European extremists targeting security forces and symbols of state to discredit, take vengeance or destabilize society.
An assault on a soldier in February at the Paris Louvre museum by a man wielding a machete also had no obvious impact on this year's opinion polls, which have consistently said that voters see unemployment and trustworthiness of politicians as bigger issues.
He said more than 50,000 police and gendarmes and 7,000 soldiers would be on duty for Sunday's first-round vote in the two-stage election, and nothing could be allowed to "hamper this democratic moment".